Tool-adjusting means



Feb. 13, 1945. -H. H. FR EEMAN 2,369,555-

TOOL ADJUSTING MEAN S Filed 00:. 12, 1942 Patented Feb. 13,1945

' UNITED STATE S t PATENT" OFFICE; 1 I

,TOOL-ADJUSTING'MEANS' V l Harry Howard Freeman, Teddington, England ApplicationOctober 12 1942', Serial No. 461,730

, ,InGreat Britain October 8, 1941 'ZClaims. (01; 29-96) otherwise operating upon a workpiece, generally of metal, is usually adjusted in its tool-holder by slackening the set screws, by whichit. is held in the tool-holder, and one orvmore taps are applied to the rear end of the cutter in' order to advance its cutting point or edge. 1 w v I ,When it is necessary to work to fine-dimensions the results obtained are not always satisfactory, and the operationis tedious as itis fre-- quently necessary to advance the cutter a num-v ber of times before thefinal cut, is :obtained, whilst as the advance of the cutter is, effected byguesswork the final cutmay be too deeptthus resulting both in waste of time and material.

Itjis the object of the present invention to provide a device whereby a cutter may be advanced with a fine and accurate adjustment. According to the present invention a tool-hold er is provided adjacent the toolrwith a screw threaded hole of predeterminedp'itch with which engages a head screw of -corresponding pitch, the 7 head of the screw being adapted to bear against:

therear end of the tool, so that when the'screw is'screwed into the hole, the tool is advanced a corresponding amount, The head may be suitably shaped, for-example square or hexagonal, for engagement by a spanner, or'for engagement by any suitable 'toolor even by hand. The pitch of the screw and the angle of turning of the head determines the amount of advance of the tool.

The screw threads may be micrometer threads whilst the head of the screw may be graduated, the graduations co-operating with a suitable mark on the tool-holder. By means of an arrangement of this character fine adjustments of the tool can be made.

A co-operating projection and groove may be' provided in the screw and tool so that as the screw is unscrewed it retracts the tool. For this purpose the tool may be provided with a projection which engages with an annular groove If desired a recess may be provided in the tool at a short distance-irom'the rear end thereof,

thisrecess' being engaged by a collar on the I screw, the collar being spaced from the head of the screw a distance equalto thespacing of the recess from the rear endof the tool.

In order to ensure that the tool is moved in a parallel plane by the head, aplate is secured to the body by spring-loaded fixing screws and is provided with a projection which fits into the I slot and bears against the tool in the slot.

The invention will now be described by way of example as applied to a knee tool with reference to the accompanying drawing, wherein:

Figure 1 is' a perspective view of a knee tool;

- Figure 2 shows a side View ofv a modified form of adjusting screw; l K Figure 3 shows-a side view of a tool for use in connection with the adjusting screw-shown in Figure 2; and

Figures 4- and 5 show a face View and an end view of a guide plate.' I

, In Figure .1 is shown a knee tool provided with a body I in which is secured a shank 2 for mounting the tool on a capstan or turret lathe.- The body 2 for receiving the tool 3 is provided in the usual manner, with a recess 4 in which the cutter 3 is clamped by two set screws 5.

In the body of the tool, adjacent the cutter 3 is drilled a hole :B'which is provided with a micrometer pitch thread. Into'thev hole 5 is screweda screw 1 of corresponding pitch which isprovided with a head 8 adapted to bear against therear end o-f the cutter 3.

',-The head 8 as shown is of truncated shape, the base bearing against the end of the cutter 3, whilst the conical surface is graduated, as indicated at 9. The graduations are adapted to co-operate with a suitable mark ID on the body lofthetoolr v Foradvancing the cutter 3, the set screws 5 are slackened and the micrometer screw 1-is turned through the amount of advance of the cutter 3 required, whereupon the set screws 5 are, again tightened. In this manner the cutter 3 can-be advanced through any desired amount. To facilitate turning the micrometer screw 1; it may be provided at its outer end with a diametral groove H for engagement by a screwmay be such that a complete revolution thereof.

produces an advance of the cutter 3 of .025", resulting in a reduction of the diameter of the hexagonal head or with a diametral recess, the

angular turning movement and pitch serving'to determine the amount of advance.

When it is also desired to make provision for retracting the cutter 3"when the screw 1 is unscrewed, the cutter 3 is provided adjacent its rear end with a projection 12 (Figure 3), such as a.

hardened pin, which engages with an annular groove i3 (Figure 2) provided in the screw 1 adjacent the inner face of the head 8 of'the screw 1.

As shown in Figure "3 the annular groove I3 is formed by providing .the screw 1 with an annular collar H, which is spaced at sufiicient distance from the inner face of the screw head 8 so as to accommodate the projection l2.

In an alternative arrangement the cutter 3 may be provided in the face thereof, adapted to lie adjacent the screw 1, with a recess, this recess being'located at the same distance from the end of the cutter 3 as the collar l4 from the screw head 8 o that it can be engaged by the collar 14.

As will readily be appreciated, it is possible with these arrangements to advance or retract the cutter 3 when the screw 1 is rotated in one. direction or the other.

For ensuring that the cutter 3 is always moved in a parallel plane, and to prevent any tendency of the cutter 3 moving from the desired plane and consequently being adjusted at an angle, a plate I5 (Figures 4 and 5) is secured to the toolholder I over the slot 4 in which the cutter 3 is mounted, by means of four spring-loaded fixing screws, which engage with tapped holes 16 in the body I. The :plate I5 is provided with four clearance holes I I so positioned that two of the screws engage with the tool-holder l on each side of the slot 4. The plate I5 is provided with a projection l8 extending the full length of the plate 15 and machined to fit the slot 4 and bear against the cutter 3. screws, by which the. plate 15 is secured to the tool-holder I, the cutter 3 can be clamped in the adjusted position or released for the purpose of being advanced or retracted when the adjusting screw 1 is turned.

By the provision of the plate 15 with its projection l8, it is also possible to clamp the, cutter 3 in the tool-holder I in such a manner that the cutter 3 can be moved in its 5101; 4 with a varying degree of freedom.

By tightening or slackening the.

The plate [5 also ensures that the cutter 3 can be controlled in a foolproof manner over the entire range of adjustment.

In an alternative arrangement, the cutter slot 4 may be replaced by a drifted or broached hole to receive the cutter 3. This ararngement, however, does not make provision for compensating for wear or slight variations in the cross sections of various cutters.

What I claim is:

1. A tool holder, comprising a body, a shank secured to said body, said body being formed in one face thereof with a recess of rectangular cross section extending the full length of said body, a tool of rectangular cross section movable longitudinally in said recess and having its opposite ends projecting from the ends of said recess', said recess being of sufficient width to enable said tool to be inserted laterally into said recess, set screws engaging, said body for clamping the tool in said recess, said body having a threaded bore therein extending parallel with said recess, a threaded rod engaging said threaded recess, a head carried by and rigid with said rod, said head having a flat face to overlie and bear against one end of the tool and having a diameter to cause the head to substantially cover the end of the tool in any rotative position of the head, whereby rotation of the head and thereby of the rod will move the tool longitudinally in the recess in the body.

2. A tool holder, comprising a body, a shank secured to said body, said body *being formed in one face thereof with a recess of rectangular cross section extending the full length of said body, a tool of rectangular cross section movable longitudinally in said recess and having its opposite ends projecting from the ends of said recess, said recess being or sufiicient width to enable said tool to be. inserted laterally into said recess, set screws engaging said body for clamping the tool in said recess, saidbody having a threaded bore therein extendingparallel with said recess, a threaded rod engaging said threaded recess, a head carried by and rigid with said rod, said head having a flat face to overlie and bear against one end of the tool andhaving a diameter to cause the head to substantially cover the end of the tool in any rotative position of the head, whereby rota- HARRY HOWARD FREEMAN. 

